Tunneling.



T. M. MCALPINE.

TUNNELING. APPLFCATION FILED JUNE 20. 1917.

1,242,217. Patend Oct. 9,1917.

2 SHEETSSHEET 2.

' able for formmg THOMAS MALCOLM MGLPiNE, O WESTMINSILE;IIQONDON,NGlJAN Be it knownthat'I, THOMSiMICI' MCALPNE, subject of' theKing of Great Britain, residing at No; 2 Central Buildings, VVestminster in the county land, have 1nVented new and useful Improvemnts Relating t0 Tunnling, ofwhich the follow'ing'is a specification.

' 'ThiS invention relates to a methodofcontunnels" and its object' is tofi be constructedwith' less cost than l1ith cavating. and filling in .with concrete'or 0then H V alsp' ifjdesitd suitable material the sections between-the spaces previously filled in, priorto thei*e moval of the natural cote or "dumpling 1 Which oecupies the interior' of the space covfile thereof.

ered ,by the so-constructed tunnel ,arcln VariouS n1ethods0f, carr yin'g Oiit"the 'i nj vention are illustrated diagrammatically on the acompanying drawings, in Wh1ch:

Figure lis a transVerse -section, showing' on the right handside an imaginary 1sometr1c v1ew of the tunnel in course et construction.

Fig. 2 is'an imaginary' isometric view.

showing a Variation. 7

Fig. 3 is a transverse section, also showing on the right hand side an imaginary isometric view of the tunnel in course of construction by a modified niethbd, and

Fig. 4 is a corresponding fragmentary.

longitudinal section, 4

Figs. 5 and6 are diagrammatic developed plans illustrating longitudinal progrss of a tunnel constructed by a method illuStrated in Figs. 3 and ,4:.

Referring'more particularly to Fig. 1:'

a is the outer profile of the tunnel Which is to be conStructed, and b 1s the inner pro- The space between the profiles a and 79 is divided into sections, headings c are-driver; alongalternate sec ofLoiid0n', Engat the crown of tharchi alternative methods of I In these figures and small tunnels on headings 0 may be sepa'rated byf one intermediate section of the ai0h.

The X"avated set1ons"of the afch con in with conerete or other suitable"material,

more than" p ifi o o t t Pateted as shown.by the three top-m'est sections c o f tlfe; arched -pace between a'.and 6, are s milary 'excavated and filled in,so that eventually' the complete arch of the tunnel beconies niade ihconcrete;r'other suitable matrial iflsitu aioinid the dumpling 6.

Fig; 2 shows how neadings' 10" to filled i n at lthel rear of f withoutinterupt gj cbtl munication with itsa' leading'face Q the nn li then la section may. be. reixiforced like may extend into the. earth or substance which occupies the spaces d On each sides of the spaces c, with the concrete or 'other suitable niaterial which is subsequently 'after they have been exCavated.

With Figs. 1 J separated small tunnels or headings for the full length ofthe tunnel, befoi*eany part ofthe tunnel archcsm be completed.

'. Figs. 36 illustrate a.method by Which the arch Space and'filled in in Sections and the arch com- "pleted while the sectional tunnels are being progressiVely advahced ings 9 are driven. at intervals around the archspace ab. These headings g extend into the dumpling 6 to provide passages beneath the space-for the arch or al0hgsidethe space for the side walls, during both excava- .a-lateral heading fcan These,

filled in the spaces d .90 Themethod of tu11neling and Constructi ng a tunnel arch described above in :connect1o1 and2, involvesdriving the :Small tunnels or head ther jsuitaible maiterial has"been'putin, the other sections d" 5- s0 asto connect r between a and I) can be excavated tion and after filling in. These headings g; r 

